import pygame, sys, random

skier_images = ["skier_down.png", "skier_right1.png",
                "skier_right2.png", "skier_left2.png",
                "skier_left1.png"]

class SkierClass (pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.image.load("skier_down.png")
        self.rect = self.image.get_rect()
        self.rect.center = [320, 100]
        self.angle = 0

    def turn(self, direction):
        self.angle = self.angle + direction
        if self.angle < -2: self.angle = -2
        if self.angle > 2: self.angle = 2
        center = self.rect.center
        self.image = pygame.image.load(skier_images[self.angle])
        self.rect = self.image.get_rect()
        self.rect.center = center
        speed = [self.angle, 6 -abs(self.angle) * 2]
        return speed

    def move(self, speed):
        self.rect.centerx = self.rect.centerx +speed[0]
        if self.rect.centerx < 20: self.rect.centerx = 20
        if self.rect.centerx > 620: self.rect.centerx = 620

class ObstacleClass(pygame.sprite.Sprite):
    def __init__(self, image_file, location, type):
        pygame.sprite.Sprite.__init__(self)
        self.image_file = image_file
        self.image = pygame.image.load(image_file)
        self.location = location
        self.rect = self.image.get_rect()
        self.rect.center = location
        self.type = type
        self.passed = False

    def scroll(self, t_ptr):
        self.rect.centery = self.location[1] - t_ptr

def create_map(start, end):
    obstacles = pygame.sprite.Group()
    locations = []
    gates = pygame.sprite.Group()
    for i in range(10):
        row = random.randint(start, end)
        col = random.randint(0, 9)
        location = [col * 64 + 20, row * 64 + 20]
        if not (location in locations):
            locations.append(location)
            type = random.choice(["tree", "flag"])
            if type == "tree": img = "skier_tree.png"
            elif type == "flag": img = "skier_flag.png"
            obstacle = ObstacleClass(img, location, type)
            obstacles.add(obstacle)
    return obstacles
def animate():
    screen.fill([255, 255, 255])
    pygame.display.update(obstacles.draw(screen))
    screen.blit(skier.image, skier.rect)
    screen.blit(score_text, [10, 10])
    pygame.display.flip()

def updateObstacleGroup(map0, map1):
    obstacles = pygame.sprite.Group()
    for ob in map0: obstacles.add(ob)
    for ob in map1: obstacles.add(ob)
    return obstacles

pygame.init()
screen = pygame.display.set_mode([640, 640])
clock = pygame.time.Clock()
skier = SkierClass()
speed = [0, 6]
map_position = 0
points = 0
map0 = create_map(20, 29)
map1 = create_map(10, 19)
activeMap = 0
obstacles = updateObstacleGroup(map0, map1)
font = pygame.font.Font(None, 50)


while True:
    clock.tick(30)
    for event in pygame.event.get():
        if event.type == pygame.QUIT: sys.exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                speed = skier.turn(-1)
            elif event.key == pygame.K_RIGHT:
                speed = skier.turn(1)
    skier.move(speed)
    map_position += speed[1]

    if map_position >= 640 and activeMap == 0:
        activeMap = 1
        map0 = create_map(20,29)
        obstacles = updateObstacleGroup(map0,map1)
    if map_position >=1280 and activeMap == 1:
        activeMap = 0     
        for ob in map0:
            ob.location[1] = ob.location[1] - 1280
        map_position = map_position - 1280
        map1 = create_map(10, 19)
        obstacles = updateObstacleGroup(map0, map1)

    for obstacle in obstacles:
        obstacle.scroll(map_position)

        hit =  pygame.sprite.spritecollide(skier, obstacles, False)
        if hit:
            if hit[0].type == "tree" and not hit[0].passed:
                points = points - 100
                skier.image = pygame.image.load("skier_crash.png")
                animate()
                pygame.time.delay(1000)
                skier.image = pygame.image.load("skier_down.png")
                skier.angle = 0
                speed = [0, 6]
                hit[0].passed = True
            elif hit[0].type == "flag" and not hit[0].passed:
                points += 10
                obstacles.remove(hit[0])


        score_text = font.render("Score: " +str(points), 1, (0, 0, 0))
        animate()
            
